From 5ec679a0fa2e26c058a8094836d80e4e989f74d5 Mon Sep 17 00:00:00 2001
From: Xin Guan <a18772@motorola.com>
Date: Thu, 21 Aug 2014 13:05:34 -0500
Subject: [PATCH] Fix crash in TranserPipe.

Sometimes the pipe has been closed when it's thread tries to access

E AndroidRuntime: *** FATAL EXCEPTION IN SYSTEM PROCESS: TransferPipe
E AndroidRuntime: java.lang.NullPointerException: Attempt to invoke virtual method 'java.io.FileDescriptor android.os.ParcelFileDescriptor.getFileDescriptor()' on a null object reference
E AndroidRuntime: 	at com.android.internal.os.TransferPipe.run(TransferPipe.java:184)
E AndroidRuntime: 	at java.lang.Thread.run(Thread.java:818)

Change-Id: I0fcd4a3334b49972903f2cb0edb51323ba3f49e5
---
 .../com/android/internal/os/TransferPipe.java | 20 +++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/core/java/com/android/internal/os/TransferPipe.java b/core/java/com/android/internal/os/TransferPipe.java
index 068d9148e2190..e76b395e9e2d4 100644
--- a/core/java/com/android/internal/os/TransferPipe.java
+++ b/core/java/com/android/internal/os/TransferPipe.java
@@ -174,15 +174,27 @@ public final class TransferPipe implements Runnable {
     }
 
     public void kill() {
-        closeFd(0);
-        closeFd(1);
+        synchronized (this) {
+            closeFd(0);
+            closeFd(1);
+        }
     }
 
     @Override
     public void run() {
         final byte[] buffer = new byte[1024];
-        final FileInputStream fis = new FileInputStream(getReadFd().getFileDescriptor());
-        final FileOutputStream fos = new FileOutputStream(mOutFd);
+        final FileInputStream fis;
+        final FileOutputStream fos;
+
+        synchronized (this) {
+            ParcelFileDescriptor readFd = getReadFd();
+            if (readFd == null) {
+                Slog.w(TAG, "Pipe has been closed...");
+                return;
+            }
+            fis = new FileInputStream(readFd.getFileDescriptor());
+            fos = new FileOutputStream(mOutFd);
+        }
 
         if (DEBUG) Slog.i(TAG, "Ready to read pipe...");
         byte[] bufferPrefix = null;